diff --git a/backend/timed/projects/serializers.py b/backend/timed/projects/serializers.py
index b76ec501..4603c355 100644
--- a/backend/timed/projects/serializers.py
+++ b/backend/timed/projects/serializers.py
@@ -139,6 +139,9 @@ def get_root_meta(self, _resource, many):
             queryset = Report.objects.filter(task=self.instance)
             data = queryset.aggregate(spent_time=Sum("duration"))
             data["spent_time"] = duration_string(data["spent_time"] or timedelta(0))
+            billable_data = queryset.filter(not_billable=False, review=False).aggregate(spent_billable=Sum("duration"))
+            data["spent_billable"] = duration_string(billable_data["spent_billable"] or timedelta(0))
+
             return data
 
         return {}